Work machines, such as backhoes, typically include an implement assembly attached to a stick assembly. Backhoes are typically utilized for various work functions. For example, a backhoe may be used to move large amounts of gravel for a period of time, and then used to dig a hole or a ditch. When the work function of the backhoe is altered as described above, it may be necessary to change the implement assembly in order for the work function to be performed properly. For example, one type of implement assembly may be attached to the stick assembly for scooping and moving gravel, and another type of implement assembly attached to the stick assembly for digging a ditch. Detaching one implement assembly from the stick assembly and attaching another is a problem because of the time and labor expended in the changeover.
One approach to addressing the above described problem is to attach a coupler to the backhoe stick assembly and then attach the implement assembly to the coupler. The coupler facilitates the coupling and decoupling between the stick assembly and the implement assembly, and thus decreases the amount of time and labor expended changing from one implement assembly to another.
However, the design of many couplers and stick assemblies cause serious performance problems for implement assemblies. For example, some couplers limit the degree of rotation of the implement assembly relative to the stick assembly as compared to when no coupler is used. Therefore, for certain work functions (e.g. those work functions requiring a greater degree of rotation of the bucket relative to the stick assembly), having a coupler attached to the stick assembly interferes with the performance of the work function. In addition, the use of some couplers results in the implement assembly being rotated relative to the stick with less force. Rotating the implement assembly with less force can also cause problems when performing certain work functions.
What is needed therefore is a work machine which overcomes the above-mentioned performance problem.